Buzzer

[stixx]

I have a 1988 125 force outboard on an older bayliner. It idled for less than five minutes. I slowly moved around the marina then the alarm (buzzing) sounded. I shut it down for about 5 mins to let it cool down. It continued to sound alarm after that. I decided to drive it for a few mins to cool it down. The alarm stopped.
Later on we stopped to fish and alarm sounded again for a few mins then stopped once it cooled.
I'm on Lake Scugog, Ontario Canada it a shallow weedy lake.
-I've recently changed the fuel to oil ratio from what its ran on for a long time 30:1. It's now to 50:1. Could this make the alarm sound ?
What should I do next?
Ps. I'm new to boating and inherited this boat.

Thanks

 

[SkiDad]

you need to change the impeller b/c it's not pumping water enough at low speeds - the motor is overheating some. No damage done but don't run it like that. There is a link in the FAQ for force at top of this forum on how to do it.

 

[mla2ofus]

My 90 HP force did that right out the gate w/ a rebuilt LU the PO installed. I removed the LU and the impeller was new also.Even w/ plenty of water coming out the pee hole at idle it would set off the alarm. I tried putting a thin piece of cardboard between the sensor and the engine to no avail. I finally just disconnected the sensor and keep a close watch on the pee hole. I may someday regret it but it was the only cure I could find. I'm not recommending you do this just saying what I decided to do to cure the problem.
Mike

 

[Jiggz]

As mentioned, drop the LU and check the status of the impeller. If you find it with missing vanes, replace it and then you need to check the water ports to make sure the missing piece is not creating a blockage. As for the alarm not stopping, check make sure the t-stat is still operating properly or even better remove for now to see if that will silence the buzzer. If not, check the wiring (orange) on the engine head to make sure it is not stripped and grounding to the engine block.

 

[stixx]

Thanks for the advice everyone. I'll check the post with the directions for repair and see if I should do it or bring it in for repairs.

 

[Frank Acampora]

Unless you have 10 thumbs, do it yourself.

Now, if a new impeller does not cure the low speed overheat, there may be a build-up of sand in the exhaust cooling passages. To check this you would need to remove the exhaust cover--not recommended unless absolutely necessary.

 

[tommarvin]

take the thermoswitch out, put the end only in a pan of cold water ,slowly heat the water, when does the buzzer sound ? it should buzz close to 180 F

 

[Frank Acampora]

UH! You can't do that. You need a jumper wire from the thermoswitch to the block. The thermoswitch must be grounded to the block. Remember: Power flows from the ignition switch to the buzzer but it has no where to go. The other wire on the buzzer goes to the engine and then the thermoswitch. When the switch heats up past a certain point a bimetal contact bends and grounds to the block, completing the circuit. The buzzer then sounds.